KR20230022397A - Curable resin, curable resin composition, and cured product - Google Patents

Abstract

By using a curable resin having a specific structure, cured products having excellent heat resistance and dielectric properties (low dielectric properties), prepregs having these properties, circuit boards, build-up films, semiconductor encapsulants, and semiconductor devices are provided. aims to do Specifically, it relates to a curable resin characterized by having a structural unit (1) represented by the following general formula (1) and a terminal structure (2) represented by the following general formula (2) (the above general formula ( In 1) and (2), details of R ₁ , R ₂ , R ₃ , k and X are as described in the text).

Description

Curable resin, curable resin composition, and cured product

The present invention relates to a curable resin having a specific structure, a curable resin composition containing the curable resin, and a cured product obtained from the curable resin composition.

Accompanying the recent increase in the amount of information communication, information communication in the high frequency band has been actively conducted, and in order to reduce transmission loss in the high frequency band, more excellent electrical characteristics, among others, having a low dielectric constant and a low dielectric loss tangent Electrical insulating materials have been in demand.

In addition, since printed circuit boards or electronic components using these electrical insulation materials are exposed to high-temperature solder reflow during mounting, materials exhibiting high glass transition temperature and excellent heat resistance are required, especially from the viewpoint of environmental problems in recent years. , since lead-free solder having a high melting point is used, demand for an electrical insulating material having higher heat resistance is increasing.

In response to these demands, conventionally, vinyl group-containing curable resins having various chemical structures have been proposed. As such a curable resin, curable resins such as divinylbenzyl ether of bisphenol or polyvinylbenzyl ether of novolak have been proposed, for example (see Patent Documents 1 and 2, for example). However, these vinylbenzyl ethers cannot impart a cured product having sufficiently low dielectric properties, and the resulting cured product is stable in a high frequency band and has problems in use. In addition, divinylbenzyl ether of bisphenol has sufficient heat resistance. It couldn't be higher.

Regarding vinyl benzyl ether having improved properties, some polyvinyl benzyl ethers having specific structures have been proposed in order to improve dielectric properties and the like (for example, see Patent Documents 3 to 5). However, although attempts have been made to suppress the dielectric loss tangent and improve heat resistance, these characteristics cannot yet be said to be sufficiently improved, and further improvement in characteristics is desired.

As described above, the conventional curable resin containing a vinyl group including polyvinylbenzyl ether has a low dielectric loss tangent required for electrical insulation material applications, particularly high-frequency electrical insulation materials applications, and heat resistance that can withstand lead-free solder processing. It did not give a hardened|cured material to combine.

Japanese Patent Laid-Open No. 63-68537 Japanese Unexamined Publication No. 64-65110 Japanese Patent Publication No. 1-503238 Japanese Patent Laid-Open No. 9-31006 Japanese Patent Laid-Open No. 2005-314556

Therefore, the problem to be solved by the present invention is to provide a cured product excellent in heat resistance (high glass transition temperature) and low dielectric properties by using a curable resin having a specific structure.

Then, the inventors of the present invention, in order to solve the above problems, as a result of intensive examination, a curable resin that can contribute to heat resistance and low dielectric characteristics, and a cured product obtained from a curable resin composition containing the curable resin are heat resistant .

That is, the present invention relates to a curable resin characterized by having a structural unit (1) represented by the following general formula (1) and a terminal structure (2) represented by the following general formula (2).

(In the above formulas (1) and (2), R ₁ independently represents an alkyl group having 1 to 12 carbon atoms, an aryl group, an aralkyl group, or a cycloalkyl group, and k represents an integer of 1 to 3 R ₂ each independently represents a hydrogen atom or a methyl group X represents a (meth)acryloyloxy group, a vinylbenzyl ether group, or an allyl ether group. , R ₃ each independently represents an alkyl group having 1 to 12 carbon atoms, an aryl group, an aralkyl group, a cycloalkyl group, or an alkenyl group)

As for the curable resin of the present invention, the general formula (1) is preferably represented by the following general formula (1-1).

As for the curable resin of the present invention, the general formula (2) is preferably represented by the following general formula (2-1).

(In the above general formula (2-1), R ₄ represents a hydrogen atom, a methyl group, or a phenyl group, and R ₅ represents an alkyl group having 1 to 4 carbon atoms)

In the curable resin of the present invention, the general formula (1) is represented by the following general formula (1-2), and the general formula (2) is the following general formula (2-2) or (2-3 ) is preferably indicated.

(In Formulas (1-2), (2-2), and (2-3), R ₆ is each independently a hydrogen atom, an alkyl group having 1 to 12 carbon atoms, an aryl group, an aralkyl group, or , represents a cycloalkyl group)

It is preferable that the weight average molecular weight of curable resin of this invention is 500-50000.

The present invention relates to a curable resin composition containing the curable resin.

This invention relates to the hardened|cured material which carried out the hardening reaction of the said curable resin composition.

Since the curable resin of the present invention can contribute to heat resistance and low dielectric characteristics, a cured product obtained from the curable resin composition containing the curable resin has excellent heat resistance and low dielectric characteristics (especially low dielectric loss tangent). and useful

Hereinafter, the present invention will be described in detail.

<curable resin>

The present invention relates to a curable resin characterized by having a structural unit (1) represented by the following general formula (1) and a terminal structure (2) represented by the following general formula (2).

(In the above general formulas (1) and (2), R ₁ independently represents an alkyl group having 1 to 12 carbon atoms, an aryl group, an aralkyl group, or a cycloalkyl group, and k represents an integer of 1 to 3 R ₂ Each independently represents a hydrogen atom or a methyl group X represents a (meth)acryloyloxy group, a vinylbenzyl ether group, or an allyl ether group. ₃ each independently represents an alkyl group having 1 to 12 carbon atoms, an aryl group, an aralkyl group, a cycloalkyl group, or an alkenyl group)

When the curable resin has a specific structure of the terminal structure and the main chain structure, the ratio of polar functional groups in the structure of the curable resin is reduced, and a cured product produced using the curable resin has a low dielectric Since it is excellent in characteristics, it is preferable. Moreover, the hardened|cured material obtained by having a crosslinking group in the said curable resin is excellent in heat resistance, and is preferable.

In the general formula (1), each R ₁ independently represents an alkyl group, an aryl group, an aralkyl group or a cycloalkyl group having 1 to 12 carbon atoms, preferably an alkyl group having 1 to 6 carbon atoms, an aryl group, Or, it is a cycloalkyl group. When the R ₁ is an alkyl group having 1 to 12 carbon atoms, etc., the planarity near the benzene ring in the general formula (1) is reduced, and the melting point is lowered while the solvent solubility is improved due to the decrease in crystallinity. do.

In the said general formula (1), k represents an integer of 1-3, Preferably it is an integer of 1-2. When k is within the above range, the flatness near the benzene ring in the above general formula (1) is reduced, and the melting point is lowered while the solvent solubility is improved due to the decrease in crystallinity, which is a preferable aspect.

In the above general formula (1), R ₂ is each independently a hydrogen atom or a methyl group. When R ₂ is a hydrogen atom or the like, the dielectric constant is lowered, which is a preferable aspect.

In the above general formula (1), X is a (meth)acryloyloxy group, a vinylbenzyl ether group, or an allyl ether group, preferably a (meth)acryloyloxy group, more preferably a meta It is a acryloyloxy group. By having the said crosslinking group in the said curable resin, the hardened|cured material which has a low dielectric loss tangent is obtained, and it becomes a preferable aspect. In addition, since the methacryloyloxy group contains a methyl group in the structure of the curable resin compared to other crosslinking groups (for example, ether groups that are polar groups such as vinylbenzyl ether group and allyl ether group), steric hindrance This is preferable because it is presumed that the molecular motility becomes lower as , and a cured product with a lower dielectric loss tangent is obtained. Moreover, when there are multiple crosslinking groups, crosslinking density increases and heat resistance improves.

In addition, although the crosslinking group X is also a polar group, the proximity of the substituent R ₁ causes steric hindrance, suppresses the molecular mobility of X, and lowers the dielectric loss tangent of the resulting cured product, which is a preferable embodiment.

In the general formula (2), each R ₃ independently represents an alkyl group, an aryl group, an aralkyl group, a cycloalkyl group, or an alkenyl group having 1 to 12 carbon atoms, preferably an alkyl group having 1 to 10 carbon atoms; It is an aryl group or a cycloalkyl group. When the R ₃ is an alkyl group having 1 to 12 carbon atoms, etc., the flatness near the benzene ring in the general formula (2) is reduced, and the melting point is lowered while the solvent solubility is improved due to the decrease in crystallinity. do. In addition, although the crosslinking group X is also a polar group, the adjacent substituent R ₃ causes steric hindrance, suppresses the molecular mobility of X, and lowers the dielectric loss tangent of the resulting cured product, which is a preferable embodiment.

The curable resin of the present invention is characterized by containing the above general formulas (1) and (2), has a structure in which the above structural unit (1) is repeated, and has a terminal structure based on the above general formula (2). However, as structures (or structural units) other than the above structural unit (1) and terminal structure (2), phenylethylidene skeleton (structure), indane skeleton (structure), dicyclopentadiene skeleton (structure), You may contain structures (or structural units), such as an aralkyl group (structure) which has a substituent. That is, the structural unit 1 may form a block structure, or may form a random structure together with other structural units as long as the characteristics of the present invention are not affected. Since the phenylethylidene backbone (structure) other than the structural unit (1) and the terminal structure (2) has a small polarity and does not have a structure that increases the dielectric constant or dielectric loss tangent, especially the curable resin in the present invention does not affect the properties of

As for the curable resin of the present invention, the general formula (1) is preferably represented by the following general formula (1-1).

As for the curable resin of the present invention, the general formula (2) is preferably represented by the following general formula (2-1).

In the general formula (2-1), R ₄ is preferably represented by a hydrogen atom, a methyl group, or a phenyl group, more preferably a hydrogen atom or a methyl group, and R ₅ is an alkyl group having 1 to 4 carbon atoms. What is displayed is preferable, and what is a C1-C2 alkyl group is more preferable. When the R ₄ is a hydrogen atom or the like, the dielectric loss tangent is lowered, which is a preferable aspect, and when the R ₅ is an alkyl group or the like, the dielectric loss tangent is lowered, which is a preferable aspect.

In the curable resin of the present invention, the general formula (1) is represented by the following general formula (1-2), and the general formula (2) is represented by the following general formula (2-2) or (2-3) It is desirable to display

In Formulas (1-2), (2-2), and (2-3), R ₆ is each independently a hydrogen atom, an alkyl group having 1 to 12 carbon atoms, an aryl group, an aralkyl group, or It is preferably represented by a cycloalkyl group, and more preferably represented by a hydrogen atom, an alkyl group having 1 to 6 carbon atoms, an aryl group, or a cycloalkyl group. When the R ₆ is a hydrogen atom or the like, the dielectric loss tangent is lowered, which is a preferable aspect.

In the general formulas (1) to (2-3), the same symbols, the same substituents, and the same functional groups (k, X, R ₁ , etc.) are common. In addition, the same applies to the following general formulas (3-1) to (7) described later.

<Method for producing intermediate phenolic compound>

As a method for producing the curable resin, first, a method for producing an intermediate phenolic compound as a raw material (precursor) of the curable resin will be described below.

As a method for producing the intermediate phenolic compound, an aralkyl compound represented by the following general formula (3-1) or (3-2) (hereinafter sometimes referred to as "compound (a)"), the following general formula ( The reaction product (c) obtained by mixing the phenol represented by 4) or a derivative thereof (hereinafter sometimes referred to as "compound (b)") and reacting in the presence of an acid catalyst, has the following general formula (5-1) Or by reacting the aralkyl compound represented by (5-2) (hereinafter sometimes referred to as "compound (d)"), the structural unit (6) represented by the following general formula and the following general formula (7) The intermediate phenolic compound having a terminal structure represented by can be obtained.

In addition, as a method for producing the intermediate phenolic compound, it is also possible to simultaneously introduce the compound (b) and the compound (d) to synthesize the intermediate phenolic compound in one-pot.

Moreover, it is preferable that Y in the said General formula (3-1) is a halogen atom, a hydroxyl group, or an oxyalkyl group, and it is more preferable that it is a hydroxyl group.

(3-1)

(3-2)

(4)

(5-1)

(5-2)

Specific examples of the compound (a) include 1,2-di(chloromethyl)benzene, 1,2-di(bromomethyl)benzene, 1,3-di(chloromethyl)benzene, and 1,3-di(fluoromethyl)benzene. Romethyl)benzene, 1,4-di(chloromethyl)benzene, 1,4-di(bromomethyl)benzene, 1,4-di(fluoromethyl)benzene, 1,4-di(chloromethyl)- 2,5-dimethylbenzene, 1,3-di(chloromethyl)-4,6-dimethylbenzene, 1,3-di(chloromethyl)-2,4-dimethylbenzene, 4,4'-bis(chloromethyl ) Biphenyl, 2,2'-bis (chloromethyl) biphenyl, 2,4'-bis (chloromethyl) biphenyl, 2,3'-bis (chloromethyl) biphenyl, 4,4'-bis ( Bromomethyl) biphenyl, 4,4'-bis (chloromethyl) diphenyl ether, 2,7-di (chloromethyl) naphthalene, p-xylylene glycol, m-xylene glycol, 1,4-di ( 2-hydroxy-2-ethyl)benzene, 4,4'-bis(dimethylol)biphenyl, 2,4'-bis(dimethylol)biphenyl, 4,4'-bis(2-hydroxy-2 -Propyl)biphenyl, 2,4'-bis(2-hydroxy-2-propyl)biphenyl, 1,4'-di(methoxymethyl)benzene, 1,4'-di(ethoxymethyl)benzene , 1,4'-di (isopropoxy) benzene, 1,4'-di (butoxy) benzene, 1,3'-di (methoxymethyl) benzene, 1,3'-di (ethoxymethyl) Benzene, 1,3'-di(isopropoxy)benzene, 1,3'-di(butoxy)benzene, 1,4-di(2-methoxy-2-ethyl)benzene, 1,4-di( 2-hydroxy-2-ethyl) benzene, 1,4-di (2-ethoxy-2-ethyl) benzene, 4,4'-bis (methoxymethyl) biphenyl, 2,4'-bis (methyl) Toxymethyl) biphenyl, 2,2'-bis (methoxymethyl) biphenyl, 2,3'-bis (methoxymethyl) biphenyl, 3,3'-bis (methoxymethyl) biphenyl, 3, 4'-bis (methoxymethyl) biphenyl, 4,4'-bis (ethoxymethyl) biphenyl, 2,4'-bis (ethoxymethyl) biphenyl, 4,4'-bis (isopropoxy ) Methylbiphenyl, 2,4'-bis(isopropoxy)methylbiphenyl, bis(1-methoxy-1-ethyl)biphenyl, bis(1-methoxy-1-ethyl)biphenyl, bis( 1-isopropoxy-1-ethyl)biphenyl, bis(2-hydroxy-2-propyl)biphenyl, bis(2-methoxy-2-propyl)biphenyl, bis(2-isopropoxy-2 -Propyl)biphenyl, 1,3-bis(α-hydride) hydroxyisopropyl)benzene, 1,4-bis(α-hydroxyisopropyl)benzene, p-divinylbenzene, m-divinylbenzene, 4,4'-bis(vinyl)biphenyl, 1,3-bis (1-hydroxyethyl) benzene, 1,4-bis (1-hydroxyethyl) benzene, etc. are mentioned. These compounds (a) may be used independently, respectively, and may use 2 or more types together. Among them, as compound (a), from the viewpoint of industrial availability, for example, p-xylylene glycol, m-xylene glycol, 1,3-bis(α-hydroxyisopropyl)benzene, It becomes a more preferable aspect to use 1, 4-bis ((alpha)-hydroxyisopropyl) benzene, p-divinylbenzene, and m-divinylbenzene.

Although it does not specifically limit as said compound (b), Specifically, cresols, such as o-cresol, m-cresol, and p-cresol; 2,3-xylenol, 2,4-xylenol, 2,5-xylenol, 2,6-xylenol (2,6-dimethylphenol), 3,4-xylenol, 3, xylenols such as 5-xylenol and 3,6-xylenol; 2,3,5-trimethylphenol, 2,3,6-trimethylphenol; ethylphenols such as o-ethylphenol (2-ethylphenol), m-ethylphenol, and p-ethylphenol; butyl phenols such as isopropyl phenol, butyl phenol, and p-t-butyl phenol; alkylphenols such as p-pentylphenol, p-octylphenol, p-nonylphenol, and p-cumylphenol; and monosubstituted phenols such as o-phenylphenol (2-phenylphenol), p-phenylphenol, 2-cyclohexylphenol, and 2-benzylphenol. These compounds (b) may be used independently, respectively, or may use 2 or more types together. Among them, it is a more preferable aspect to use, for example, cresol or xylenol as the compound (b) from the viewpoint of industrial availability. However, if the steric hindrance is too great, there is a concern that the reactivity of the intermediate phenol compound at the time of synthesis may be inhibited. Therefore, for example, it is preferable to use a compound (b) having a methyl group, an ethyl group, a cyclohexyl group, or a phenyl group. desirable.

In the method for producing the intermediate phenolic compound, the molar ratio of the compound (a) and the compound (b) of the compound (b) to the compound (a) (compound (b)/compound (a)), Preferably, it is 2.5/1 to 1.05/1, more preferably 2/1 to 1.1/1, and reacted in the presence of an acid catalyst to react with the compound (a) and the compound (b) Product (c) can be obtained.

Examples of the acid catalyst used in the reaction include inorganic acids such as phosphoric acid, hydrochloric acid and sulfuric acid, organic acids such as oxalic acid, benzenesulfonic acid, toluenesulfonic acid, methanesulfonic acid and fluoromethanesulfonic acid, activated clay and acid clay , silica, alumina, zeolite, solid acids such as strongly acidic ion exchange resins, heteropolyacids, etc., but oxalic acid and benzene, which are homogeneous catalysts that can be easily removed by neutralization with a base and washing with water after reaction. It is preferable to use sulfonic acid, toluenesulfonic acid, methanesulfonic acid, or fluoromethanesulfonic acid.

The compounding amount of the acid catalyst is blended in the range of 0.001 to 40 parts by mass with respect to 100 parts by mass of the total amount of the compound (a) and the compound (b) as the first raw material, but from the viewpoint of handling property and economy. , 0.001 to 25 parts by mass is preferable.

The reaction temperature may normally be in the range of 80 to 200 ° C., but is preferably 100 to 150 ° C. in order to suppress the formation of isomer structures, avoid side reactions such as thermal decomposition, and obtain high-purity intermediate phenolic compounds.

As the reaction time, since the reaction does not proceed completely in a short time, and side reactions such as a thermal decomposition reaction of the product occur in a long time, it is usually in the range of 0.5 to 24 hours in total under the above reaction temperature conditions. , preferably in the range of 0.5 to 15 hours in total.

Specific examples of the compound (d) (functioning as a terminal blocker) are not particularly limited, but specifically include styrene, styrene dimer, α-methylstyrene, α-methylstyrene dimer, methylstyrene, vinyltoluene), ethyl Styrene or styrene derivatives, such as styrene and t-butyl styrene, vinyl naphthalene, vinyl biphenyl, diphenyl ethylene, 1-octene, etc. are mentioned.

The compounding amount of the compound (d) is blended in the range of 1 to 200 parts by mass with respect to 100 parts by mass of the total amount of the compound (a) and the compound (b) as the first raw material, but from the point of reactivity , 10 to 100 parts by mass is preferable.

The reaction temperature between the compound (b) and the reaction product (c) may normally be in the range of 80 to 200 ° C., but in order to obtain a high-purity intermediate phenolic compound by suppressing the formation of an isomer structure and avoiding side reactions such as thermal decomposition, 100-150 degreeC is preferable.

As the reaction time, since the reaction does not proceed completely in a short time, and side reactions such as a thermal decomposition reaction of the product occur in a long time, it is usually in the range of 0.5 to 24 hours in total under the above reaction temperature conditions. , preferably in the range of 0.5 to 15 hours in total.

In the reaction between the reaction product (c) and the compound (d), the acid catalyst used in the reaction between the compound (a) and the compound (b) described above can be used similarly.

In the method for producing the intermediate phenolic compound, since the raw material also serves as a solvent in some cases, it is not necessary to use another solvent, but it is also possible to use a solvent. In addition, you may employ|adopt the method of carrying out reaction in the said reaction temperature range after distilling off the solvent (for example, methanol etc.) generated at the time of reaction.

Examples of the organic solvent used for synthesizing the intermediate phenol compound include ketones such as acetone, methyl ethyl ketone (MEK), methyl isobutyl ketone, cyclohexanone and acetophenone, alcohols such as 2-ethoxyethanol and methanol, Nonprotic solvents such as N,N-dimethylformamide, N,N-dimethylacetamide, dimethyl sulfoxide, N-methyl-2-pyrrolidone, acetonitrile and sulfolane, dioxane, tetrahydro and cyclic ethers such as furan, esters such as ethyl acetate and butyl acetate, and aromatic solvents such as benzene, toluene and xylene. These may be used alone or in combination.

The hydroxyl equivalent (phenol equivalent) of the intermediate phenolic compound is preferably 100 to 1000 g/eq, more preferably 200 to 500 g/eq, from the viewpoint of heat resistance. In addition, the hydroxyl equivalent (phenol equivalent) of the intermediate phenol compound is calculated by a titration method, and refers to a neutralization titration method based on JIS K0070.

<Method for producing curable resin>

A method for producing the above curable resin (introducing a (meth)acryloyloxy group, a vinylbenzyl ether group, or an allyl ether group into an intermediate phenolic compound) will be described below.

The curable resin is, in the presence of a basic or acidic catalyst, (meth)acrylic acid anhydride, (meth)acrylic acid chloride, chloromethylstyrene, chlorostyrene, allyl chloride, or allyl bromide, etc. (hereinafter referred to as , It can be obtained by a known method such as reaction with "compound (e)"). By reacting these, a crosslinking group (X) can be introduced into the intermediate phenolic compound, and thermosetting characteristics such as low dielectric constant and low dielectric loss tangent are obtained, which is a preferred embodiment.

As the compound (e) (which functions as a cross-linking group introducing agent), examples of (meth)acrylic anhydride include acrylic anhydride and methacrylic anhydride. Examples of the (meth)acrylic acid chloride include methacrylic acid chloride and acrylic acid chloride. Examples of chloromethylstyrene include p-chloromethylstyrene and m-chloromethylstyrene, and examples of chlorostyrene include p-chlorostyrene and m-chlorostyrene. Examples of allyl include 3-chloro-1-propene, and examples of allyl bromide include 3-bromo-1-propene. These may be used independently, respectively, or may be mixed and used. Among them, it is preferable to use methacrylic anhydride or methacrylic acid chloride, from which a cured product with a lower dielectric loss tangent can be obtained.

Specific examples of the basic catalyst include dimethylaminopyridine, alkaline earth metal hydroxides, alkali metal carbonates, and alkali metal hydroxides. As said acidic catalyst, a sulfuric acid, methanesulfonic acid, etc. are mentioned specifically,. In particular, dimethylaminopyridine is excellent in terms of catalytic activity.

As the reaction between the intermediate phenolic compound and the compound (e), 1 to 10 mol of the compound (e) is added to 1 mol of hydroxyl groups contained in the intermediate phenolic compound, and 0.01 to 0.2 mol of a basic catalyst is added at once. Or, the method of making it react for 1 to 40 hours at the temperature of 30-150 degreeC, adding gradually is mentioned.

In addition, when reacting with the compound (e) (introduction of a crosslinking group), the reaction rate in the synthesis of the curable resin can be increased by using an organic solvent in combination. Examples of such an organic solvent include, but are not particularly limited to, ketones such as acetone and methyl ethyl ketone, alcohols such as methanol, ethanol, 1-propyl alcohol, isopropyl alcohol, 1-butanol, secondary butanol, and tert-butanol. , cellosolves such as methyl cellosolve and ethyl cellosolve, ethers such as tetrahydrofuran, 1,4-dioxane, 1,3-dioxane, and diethoxyethane, acetonitrile, dimethyl sulfoxide, and dimethyl aprotic polar solvents such as formamide, toluene, and the like. These organic solvents may be used independently, respectively, and in order to adjust the polarity, they may be used in combination of two or more types.

After completion of the reaction with the above-described compound (e) (introduction of a crosslinking group), the reaction product is reprecipitated in a poor solvent, and then the precipitate is removed in a poor solvent at a temperature of 20 to 100 ° C., 0.1 to 5 After stirring for an hour and filtering under reduced pressure, the target curable resin can be obtained by drying the precipitate at a temperature of 40 to 80°C for 1 to 10 hours. Hexane etc. are mentioned as a poor solvent.

Further, the curable resin of the present invention is characterized by containing the above general formulas (1) and (2), has a structure in which the above structural unit (1) is repeated, and has a terminal term based on the above general formula (2). Although it is preferable that it is a structure, even if it contains a structure other than these structural unit (1) and terminal structure (2) as a side reaction by the said manufacturing method, if it does not affect the characteristics of the curable resin in this invention. , there is no particular problem.

The curable resin of the present invention preferably has a weight average molecular weight (Mw) of 500 to 50000, more preferably 500 to 20000, still more preferably 800 to 10000. When the weight average molecular weight of the curable resin is within the above range, it is preferable because workability and molding processability are excellent.

As a softening point of the said curable resin, it is preferable that it is 150 degreeC or less, and it is more preferable that it is 50-100 degreeC. When the softening point of the curable resin is within the above range, it is preferable because processability is excellent.

<Curable Resin Composition>

It is preferable that curable resin composition of this invention contains the said curable resin. The curable resin has a substituent R ₁ in the structure and -C(CH ₃ )R ₃ R ₃ in the terminal structure, so that the molecular mobility of the crosslinking group is suppressed, the dielectric loss tangent is excellent, and the structural unit By having -CR ₂ R ₂ -C ₆ H ₄ -CR ₂ R ₂ -, the free volume is reduced, the low permittivity is excellent, the flexibility is expressed, and the solvent solubility is excellent, so that the curable resin composition It is easy to manufacture, has excellent handling properties, and has a small proportion of polar functional groups in the structure of the curable resin, so that a cured product obtained using the curable resin composition has excellent low dielectric properties and is a preferable aspect.

[Other resins, etc.]

In the curable resin composition of the present invention, in addition to the above-mentioned curable resin, other resins, curing agents, curing accelerators, etc. can be used without particular limitation within a range not impairing the object of the present invention. As will be described later, the curable resin can be obtained by heating or the like without adding a curing agent. For example, when blending together other resins, etc., a curing agent or curing accelerator can be blended and used.

In addition, the curable resin composition of the present invention includes the curable resin, but in the curable resin, when X is an allyl ether group, X is a (meth)acryloyloxy group or a vinylbenzyl ether group, unlike a homopolymerization (crosslinking) Since it is not possible (a cured product cannot be obtained alone), when the X is an allyl ether group, it is necessary to use a curing agent or a curing accelerator.

[Other resins]

Examples of the other resins include alkenyl group-containing compounds such as bismaleimides, allyl ether compounds, allyl amine compounds, triallyl cyanurates, alkenyl phenol compounds, and vinyl group-containing polyolefin compounds. etc. may be added. In addition, other thermosetting resins such as thermosetting polyimide resins, epoxy resins, phenol resins, active ester resins, benzoxazine resins, cyanate resins and the like can also be appropriately incorporated depending on the purpose.

[curing agent]

Examples of the curing agent include amine-based compounds, amide-based compounds, acid anhydride-based compounds, phenol-based compounds, and cyanate ester compounds. These curing agents may be used alone or in combination of two or more.

[Curing accelerator]

Various types of curing accelerators can be used, and examples thereof include phosphorus compounds, tertiary amines, imidazoles, organic acid metal salts, Lewis acids, and amine complex salts. In particular, when used as a semiconductor encapsulating material, phosphorus compounds such as triphenylphosphine or imidazoles are preferable from the viewpoint of excellent curing properties, heat resistance, electrical properties, moisture resistance reliability, and the like. These hardening accelerators may be used independently or may use 2 or more types together.

[Flame retardant]

In the curable resin composition of the present invention, if necessary, in order to exhibit flame retardancy, a flame retardant can be blended, and among them, a non-halogen-based flame retardant that does not substantially contain a halogen atom can be blended. Examples of the non-halogen flame retardant include phosphorus-based flame retardants, nitrogen-based flame retardants, silicon-based flame retardants, inorganic flame retardants, organic metal salt-based flame retardants, and the like, and these flame retardants may be used alone or in combination of two or more.

[filler]

An inorganic filler can be blended with the curable resin composition of the present invention, if necessary. Examples of the inorganic filler include fused silica, crystalline silica, alumina, silicon nitride, and aluminum hydroxide. When the blending amount of the inorganic filler is particularly increased, it is preferable to use fused silica. Although both crushed and spherical fused silica can be used, it is preferable to mainly use spherical ones in order to increase the amount of fused silica and to suppress the increase in the melt viscosity of the molding material. In order to further increase the compounding amount of the spherical silica, it is preferable to appropriately adjust the particle size distribution of the spherical silica. In addition, when using the said curable resin composition for uses, such as the electrically conductive paste mentioned in detail below, conductive fillers, such as silver powder and copper powder, can be used.

[Other compounding agents]

Curable resin composition of this invention can add various compounding agents, such as a silane coupling agent, a mold release agent, a pigment, and an emulsifier, as needed.

<cured material>

It is preferable that the hardened|cured material of this invention is obtained by carrying out a hardening reaction of the said curable resin composition. The curable resin composition is obtained by uniformly mixing the curable resin alone or in addition to the curable resin, and each component such as the curing agent described above, and can be easily converted into a cured product by a method similar to a conventionally known method. can Examples of the cured product include molded and cured products such as laminates, cast products, adhesive layers, coating films, and films.

Examples of the curing reaction include thermal curing and ultraviolet curing. Among them, the thermal curing reaction is easily carried out even without a catalyst, but when the reaction is to be made faster, a polymerization initiator such as an organic peroxide or an azo compound; Addition of a basic catalyst such as a phosphine compound or a tertiary amine is effective. Examples thereof include benzoyl peroxide, dicumyl peroxide, azobisisobutyronitrile, triphenylphosphine, triethylamine, and imidazoles.

<Use>

Since the cured product obtained from the curable resin composition of the present invention has excellent heat resistance and low dielectric properties, it can be suitably used for heat-resistant members and electronic members. In particular, it can be suitably used for prepregs, circuit boards, semiconductor sealing materials, semiconductor devices, build-up films, build-up substrates, adhesives and resist materials. In addition, it can be suitably used also for matrix resins of fiber-reinforced resins, and is particularly suitable as highly heat-resistant prepregs. In addition, since the curable resin contained in the curable resin composition exhibits excellent solubility in various solvents, it can be made into a paint. The heat-resistant member and electronic member obtained in this way can be suitably used for various applications, and include, for example, industrial machine parts, general machine parts, parts such as automobiles, railways, and vehicles, parts related to space and aviation, electronic and electric parts, and construction. materials, containers/packaging members, daily necessities, sports/leisure products, casing members for wind power generation, and the like, but are not limited thereto.

[Example]

In the following, the present invention will be specifically explained by Examples and Comparative Examples, but "parts" and "%" are based on mass unless otherwise specified. Moreover, curable resin and the hardened|cured material obtained using the said curable resin were synthesize|combined under the conditions shown below, and measurement and evaluation were performed further about the obtained hardened|cured material under the following conditions.

<GPC measurement (evaluation of weight average molecular weight (Mw) of curable resin)>

It measured using the following measuring apparatus and measuring conditions, and obtained the GPC chart of the curable resin obtained by the synthetic method shown below. From the results of the GPC chart, the weight average molecular weight (Mw) of curable resin was calculated.

Measuring device: Tosoh Corporation "HLC-8320 GPC", Column: Tosoh Corporation guard column "HXL-L" + Tosoh Corporation "TSK-GEL G2000HXL" + Tosoh Corporation "TSK-GEL G2000HXL" manufactured by Tosoh Corporation "TSK-GEL G3000HXL" manufactured by Tosoh Corporation + "TSK-GEL G4000HXL" manufactured by Toso Corporation

Detector: RI (Differential Refractometer)

Data processing: "GPC workstation EcoSEC-WorkStation" manufactured by Tosoh Corporation

Measurement conditions: column temperature 40 ° C.

Developing solvent tetrahydrofuran

Flow rate 1.0ml/min

Standard: The following monodisperse polystyrene having a known molecular weight was used in accordance with the measurement manual of the above "GPC workstation EcoSEC-WorkStation".

(use polystyrene)

"A-500" made by Tosoh Corporation

"A-1000" manufactured by Toso Co., Ltd.

"A-2500" by Tosoh Corporation

"A-5000" manufactured by Toso Co., Ltd.

"F-1" made by Toso Co., Ltd.

"F-2" made by Toso Co., Ltd.

"F-4" made by Toso Co., Ltd.

"F-10" made by Toso Co., Ltd.

"F-20" made by Toso Co., Ltd.

"F-40" made by Toso Co., Ltd.

"F-80" made by Toso Co., Ltd.

"F-128" made by Toso Co., Ltd.

Sample: A 1.0% by mass tetrahydrofuran solution in terms of solid content of the curable resin obtained in the Synthesis Example was filtered through a microfilter (50 μl).

(Example 1)

324.4 g of o-cresol, 276.3 g of p-xylylene glycol, and 19.0 g of p-toluenesulfonic acid monohydrate were added to a 3L, 4-necked separable flask equipped with a stirrer, cooling tube, nitrogen inlet tube, and thermometer, while stirring. The temperature was raised to 150° C. and reacted for 5 hours. In the meantime, methanol produced by the reaction was removed out of the system. After that, the temperature was lowered to 120°C, 260.4 g of styrene was added dropwise over 5 hours, and the mixture was reacted to obtain an intermediate phenolic compound.

In a 100 mL, four-necked flask equipped with a stirrer, cooling pipe, nitrogen inlet pipe, and thermometer, 10.0 g of the intermediate phenolic compound synthesized above, 10.0 g of N,N-dimethylformamide, 9.2 g of 4-chloromethylstyrene, 48% 7.0 g of potassium hydroxide aqueous solution was added, and the temperature was raised to 60° C. while stirring and reacted for 20 hours. The reaction solution was poured into 100 g of methanol, and the polymer was reprecipitated. The polymer was re-dissolved in 100 g of tetrahydrofuran, poured into 100 g of methanol again, and the polymer was reprecipitated. The obtained polymer was washed twice with 100 g of methanol. Then, it was made to dry at 50 degreeC under reduced pressure for 2 hours, and curable resin (Mw: 2100) was obtained.

(Example 2)

Into a 3L, 4-necked separable flask with stirrer, cooling tube, nitrogen inlet tube and thermometer, 324.4 g of o-cresol, 388.5 g of 1,3-bis(α-hydroxyisopropyl)benzene, and p-toluenesulfonic acid 19.0 g of hydrate was added, and the temperature was raised to 150°C while stirring and reacted for 5 hours. During this time, the water generated by the reaction was removed out of the system. After that, the temperature was lowered to 120°C, 260.4 g of styrene was added dropwise over 5 hours, and the mixture was reacted to obtain an intermediate phenolic compound.

In a 100 mL, four-necked flask equipped with a stirrer, cooling pipe, nitrogen inlet pipe, and thermometer, 10.0 g of the intermediate phenolic compound synthesized above, 10.0 g of N,N-dimethylformamide, 9.2 g of 4-chloromethylstyrene, 48% 7.0 g of potassium hydroxide aqueous solution was added, and the temperature was raised to 60° C. while stirring and reacted for 20 hours. The reaction solution was poured into 100 g of methanol, and the polymer was reprecipitated. The polymer was re-dissolved in 100 g of tetrahydrofuran, poured into 100 g of methanol again, and the polymer was reprecipitated. The obtained polymer was washed twice with 100 g of methanol. Then, it was made to dry at 50 degreeC under reduced pressure for 2 hours, and curable resin (Mw: 2200) was obtained.

(Example 3)

Into a 3L, 4-necked separable flask with stirrer, cooling tube, nitrogen inlet tube and thermometer, 324.4 g of o-cresol, 332.4 g of 1,4-bis(1-hydroxyethyl)benzene, and p-toluenesulfonic acid monohydrate 19.0 g was added, and the temperature was raised to 150° C. while stirring and reacted for 5 hours. During this time, the water generated by the reaction was removed out of the system. After that, the temperature was lowered to 120°C, 260.4 g of styrene was added dropwise over 5 hours, and the mixture was reacted to obtain an intermediate phenolic compound.

In a 100 mL, four-necked flask equipped with a stirrer, cooling pipe, nitrogen inlet pipe, and thermometer, 10.0 g of the intermediate phenolic compound synthesized above, 10.0 g of N,N-dimethylformamide, 9.2 g of 4-chloromethylstyrene, 48% 7.0 g of potassium hydroxide aqueous solution was added, and the temperature was raised to 60° C. while stirring and reacted for 20 hours. The reaction solution was poured into 100 g of methanol, and the polymer was reprecipitated. The polymer was re-dissolved in 100 g of tetrahydrofuran, poured into 100 g of methanol again, and the polymer was reprecipitated. The obtained polymer was washed twice with 100 g of methanol. Then, it was made to dry at 50 degreeC under reduced pressure for 2 hours, and curable resin (Mw: 2200) was obtained.

(Example 4)

A curable resin (Mw: 2000) was obtained in the same manner as in Example 3, except that 260.4 g of styrene in Example 3 was changed to 295.5 g of α-methylstyrene.

(Example 5)

A curable resin (Mw: 1900) was obtained in the same manner as in Example 3, except that 260.4 g of styrene in Example 3 was changed to 295.5 g of 4-methylstyrene.

(Example 6)

A curable resin (Mw: 1900) was obtained in the same manner as in Example 3, except that 260.4 g of styrene in Example 3 was changed to 450.8 g of 1,1-diphenylethylene.

(Example 7)

A curable resin (Mw: 1800) was obtained in the same manner as in Example 3, except that 260.4 g of styrene in Example 3 was changed to 280.6 g of 1-octene.

(Example 8)

A curable resin (Mw: 1800) was obtained by synthesizing in the same manner as in Example 3, except that 324.4 g of o-cresol in Example 3 was changed to 366.5 g of 2-ethylphenol.

(Example 9)

A curable resin (Mw: 1800) was obtained by synthesizing in the same manner as in Example 3, except that 324.4 g of o-cresol in Example 3 was changed to 510.6 g of 2-phenylphenol.

(Example 10)

A curable resin (Mw: 1900) was obtained by synthesizing in the same manner as in Example 3, except that 324.4 g of o-cresol in Example 3 was changed to 528.8 g of 2-cyclohexylphenol.

(Example 11)

A curable resin (Mw: 2600) was obtained by synthesizing in the same manner as in Example 3, except that 324.4 g of o-cresol in Example 3 was changed to 324.4 g of p-cresol.

(Example 12)

The same method as in Example 3 except that 9.2 g of 4-chloromethylstyrene in Example 3 was changed to 9.3 g of methacrylic anhydride, and 7.0 g of 48% potassium hydroxide aqueous solution was changed to 0.2 g of 4-dimethylaminopyridine. Synthesis was performed by the above, and a curable resin (Mw: 2200) was obtained.

(Example 13)

324.4 g of o-cresol and 19.0 g of p-toluenesulfonic acid monohydrate were added to a 3L, 4-necked separable flask equipped with a stirrer, cooling tube, nitrogen inlet tube, and thermometer, and the temperature was raised to 120° C. while stirring, divinylbenzene 280.4 g was added dropwise over 5 hours to react. After that, 260.4 g of styrene was added dropwise over 5 hours and reacted to obtain an intermediate phenolic compound.

In a 100 mL, four-necked flask equipped with a stirrer, cooling pipe, nitrogen inlet pipe, and thermometer, 10.0 g of the intermediate phenolic compound synthesized above, 10.0 g of N,N-dimethylformamide, 9.2 g of 4-chloromethylstyrene, 48% 7.0 g of potassium hydroxide aqueous solution was added, and the temperature was raised to 60° C. while stirring and reacted for 20 hours. The reaction solution was poured into 100 g of methanol, and the polymer was reprecipitated. The polymer was re-dissolved in 100 g of tetrahydrofuran, poured into 100 g of methanol again, and the polymer was reprecipitated. The obtained polymer was washed twice with 100 g of methanol. Then, it was made to dry at 50 degreeC under reduced pressure for 2 hours, and curable resin (Mw: 2100) was obtained.

(Example 14)

A curable resin (Mw: 2300) was obtained in the same manner as in Example 3, except that 324.4 g of o-cresol in Example 3 was changed to 366.49 g of 2,5-xylenol.

(Example 15)

A curable resin (Mw: 2500) was obtained by synthesizing in the same manner as in Example 3, except that 324.4 g of o-cresol in Example 3 was changed to 408.54 g of 2,3,5-trimethylphenol.

(Example 16)

Synthesis was carried out in the same manner as in Example 3, except that 9.2 g of 4-chloromethylstyrene in Example 3 was changed to 7.3 g of acrylbromide, and 7.0 g of 48% potassium hydroxide aqueous solution was changed to 20.0 g of potassium carbonate. This was carried out to obtain a curable resin (Mw: 1800).

(Comparative Example 1)

282.3 g of phenol, 276.3 g of p-xylylene glycol, and 19.0 g of p-toluenesulfonic acid monohydrate were put into a 3L, 4-necked separable flask equipped with a stirrer, cooling pipe, nitrogen inlet pipe, and thermometer, and heated to 150°C while stirring. The temperature was raised and reacted for 5 hours. In the meantime, methanol produced by the reaction was removed out of the system to obtain an intermediate phenolic compound.

In a 100 mL, four-necked flask equipped with a stirrer, cooling pipe, nitrogen inlet pipe, and thermometer, 10.0 g of the intermediate phenolic compound synthesized above, 10.0 g of N,N-dimethylformamide, 9.2 g of 4-chloromethylstyrene, 48% 7.0 g of potassium hydroxide aqueous solution was added, and the temperature was raised to 60° C. while stirring and reacted for 20 hours. The reaction solution was poured into 100 g of methanol, and the polymer was reprecipitated. The polymer was re-dissolved in 100 g of tetrahydrofuran, poured into 100 g of methanol again, and the polymer was reprecipitated. The obtained polymer was washed twice with 100 g of methanol. Then, it was made to dry at 50 degreeC under reduced pressure for 2 hours, and curable resin (Mw: 2300) was obtained.

(Comparative Example 2)

324.4 g of o-cresol, 276.3 g of p-xylylene glycol, and 19.0 g of p-toluenesulfonic acid monohydrate were added to a 3L, 4-necked separable flask equipped with a stirrer, cooling tube, nitrogen inlet tube, and thermometer, while stirring. The temperature was raised to 150° C. and reacted for 5 hours. In the meantime, methanol produced by the reaction was removed out of the system to obtain an intermediate phenolic compound.

In a 100 mL, four-necked flask equipped with a stirrer, cooling pipe, nitrogen inlet pipe, and thermometer, 10.0 g of the intermediate phenolic compound synthesized above, 10.0 g of N,N-dimethylformamide, 9.2 g of 4-chloromethylstyrene, 48% 7.0 g of potassium hydroxide aqueous solution was added, and the temperature was raised to 60° C. while stirring and reacted for 20 hours. The reaction solution was poured into 100 g of methanol, and the polymer was reprecipitated. The polymer was re-dissolved in 100 g of tetrahydrofuran, poured into 100 g of methanol again, and the polymer was reprecipitated. The obtained polymer was washed twice with 100 g of methanol. Then, it was made to dry at 50 degreeC under reduced pressure for 2 hours, and curable resin (Mw: 2400) was obtained.

<Production of resin film (cured product)>

The curable resin (solid powder) obtained in Examples and Comparative Examples was placed in a 5 cm square mold, clamped with a stainless steel plate, and set by a vacuum press. It was pressurized up to 1.5 MPa under normal pressure and normal temperature. Next, after reducing the pressure to 10 torr, it was heated over 30 minutes to a temperature 50 ° C. higher than the thermal curing temperature. Furthermore, it cooled gradually to room temperature after stationary for 2 hours. As a result, a uniform resin film (cured product) having an average film thickness of 100 µm was produced.

In Example 16 (X is an allyl ether group), since homopolymerization (crosslinking) of the curable resin alone does not proceed, only production confirmation of the curable resin is performed, and evaluation based on the following resin film (cured product) is not doing

<Evaluation of dielectric characteristics>

Regarding the dielectric characteristics of the obtained resin film (cured product) in the in-plane direction, the dielectric constant and dielectric loss tangent were measured at a frequency of 10 GHz by a split post dielectric resonance method using a network analyzer N5247A from Keysight Technologies. Further, the dielectric loss tangent is 10 × 10 ^-3 or less, which poses no practical problem, preferably 5.5 × 10 ^-3 or less, and more preferably 4.5 × 10 ^-3 or less. In addition, as a permittivity, if it is 3 or less, there is no practical problem, Preferably it is 2.8 or less, More preferably, it is 2.6 or less.

<Evaluation of heat resistance (glass transition temperature)>

After observation of the exothermic peak temperature (thermal curing temperature) observed when the obtained resin film (cured product) was measured using a DSC device (Pyris Diamond) manufactured by PerkinElmer under a heating condition of 20°C/min at room temperature, , and maintained for 30 minutes at a temperature 50° C. higher than that. Next, the sample was cooled to room temperature under a temperature-decreasing condition of 20°C/min, and further heated under a temperature-raising condition of 20°C/min, and the glass transition point temperature (Tg) (°C) of the resin film (cured product) was obtained. was measured. Moreover, as long as it is 100 degreeC or more as glass transition point temperature (Tg), there is no practical problem, Preferably it is 130 degreeC or more, More preferably, it is 150 degreeC or more.

[Table 1]

Note) In Examples 1 to 10, 12, and 13, R ₁ in Table 1 above has a methyl group or the like ortho to the crosslinking group X. Further, Example 11 has a methyl group at the ortho position with respect to the crosslinking group X, and Example 14 has a methyl group at the ortho (2-) and meta position (5-) relative to the crosslinking group X. It has methyl groups at the ortho (2-), meta-position (3-), and meta-position (5-) of the 15-valent crosslinking group X.

[Table 2]

Note) In Tables 1 and 2 above, Ph represents a phenyl group and Cy represents a cyclohexyl group.

From the evaluation results in Tables 1 and 2, in all examples, the cured product obtained by using the curable resin can achieve both heat resistance and low dielectric characteristics, and is at a level that does not cause problems in practical use. I was able to confirm.

On the other hand, from the evaluation results in Table 2, in Comparative Example 1, the molecular mobility of the main chain and the terminal crosslinking group (polar site) in the obtained curable resin is high, so the dielectric loss tangent or permittivity is high, and the dielectric properties are poor. It was confirmed that the glass transition temperature (Tg) was low and the heat resistance was low because the rigidity of the main chain was low (low dielectric properties were not obtained). In Comparative Example 2, because of the high molecular mobility of the crosslinking group (polar site) at the end of the curable resin, the dielectric loss tangent and dielectric constant show high values, the dielectric properties are poor, and the rigidity of the main chain is low, so the glass transition temperature ( It was also confirmed that the Tg) was low and the heat resistance was poor.

Since the cured product obtained by using the curable resin of the present invention has excellent heat resistance and dielectric properties, it can be suitably used for heat-resistant members and electronic members, and in particular, prepregs, semiconductor sealing materials, circuit boards, and build-up materials. It can be suitably used for films, build-up substrates, etc., as well as adhesives and resist materials. In addition, it can be used suitably also for matrix resins of fiber-reinforced resins, and is suitable as highly heat-resistant prepregs.

Claims (7)

A curable resin characterized by having a structural unit (1) represented by the following general formula (1) and a terminal structure (2) represented by the following general formula (2).

(In the above formulas (1) and (2), R ₁ independently represents an alkyl group having 1 to 12 carbon atoms, an aryl group, an aralkyl group, or a cycloalkyl group, and k represents an integer of 1 to 3 indicate
R ₂ each independently represents a hydrogen atom or a methyl group. X represents a (meth)acryloyloxy group, a vinylbenzyl ether group, or an allyl ether group. In Formula (2), each R ₃ independently represents an alkyl group having 1 to 12 carbon atoms, an aryl group, an aralkyl group, a cycloalkyl group, or an alkenyl group.) According to claim 1,
A curable resin characterized in that the general formula (1) is represented by the following general formula (1-1).

According to claim 1 or 2,
A curable resin characterized in that the general formula (2) is represented by the following general formula (2-1).

(In the above general formula (2-1), R ₄ represents a hydrogen atom, a methyl group, or a phenyl group, and R ₅ represents an alkyl group having 1 to 4 carbon atoms) According to any one of claims 1 to 3,
The general formula (1) is represented by the following general formula (1-2),
The curable resin characterized in that the general formula (2) is represented by the following general formula (2-2) or (2-3).

(In Formulas (1-2), (2-2), and (2-3), R ₆ is each independently a hydrogen atom, an alkyl group having 1 to 12 carbon atoms, an aryl group, an aralkyl group, or , represents a cycloalkyl group) According to any one of claims 1 to 4,
A curable resin characterized by having a weight average molecular weight of 500 to 50000. A curable resin composition comprising the curable resin according to any one of claims 1 to 5. A cured product obtained by subjecting the curable resin composition according to claim 6 to a curing reaction.